Composite polymer structures and polymer blends are of great commercial interest because of the potential to combine the valuable attributes of a number of materials into one system. Composite laminates of two or more polymers are widely used in barrier packaging applications where the barrier characteristics of one material are combined with the low cost and mechanical properties of another. In polymer blends, combinations of barrier/cost, chemical resistance/dimensional stability, toughness/strength are achieved in a number of commercial materials.
In both composite polymer structures and polymer blends, the compatibilization of the polymer/polymer interface is of critical importance. Weak interfacial bonding between the phases results in delamination and poor mechanical properties. However, strong interfacial bonds are desired to attain the ultimate characteristics of the composite or blend.
It is well known that most polymer pairs are immiscible and do not have strong enough interactions to generate strong interfacial bonds during coextrusion or melt blending. However, several compatibilization strategies have emerged to resolve the expected poor adhesion between polymer pairs. Compatibility and adhesion can be improved by 1) incorporation of a third mutually compatible "tie-layer" between phases, 2) addition of a suitable block or graft copolymer or mutually miscible polymer which bridges the interface, or 3) promotion of in-situ grafting reactions via appropriate functionalization of one or both of the polymers.
Polyketone polymers are well known in the art. These polymers have excellent mechanical and chemical resistance properties which make them particularly attractive for the production of composite structures. However, because of the difficulty of compatibilizing the polyketone polymer/other polymer interface so that resulting bond is sufficiently strong to withstand end-use conditions, the production of polyketone polymer-based composite structures have been compromised. Therefore, methods and/or other polymeric materials which are capable of overcoming this deficiency are of great commercial interest to the industry.